1. Field of the Invention
The present invention is generally related to a control system for a marine vessel and, more particularly, to a control system that utilizes a serial bus to connect pluralities of input devices and output devices in signal communication with each other.
2. Description of the Prior Art
The control of a marine vessel, such as a pleasure craft used for fishing, water skiing, or other leisure activities, requires the implementation of many different input and output devices. For example, input signals are provided by speedometers, tachometers, depth finders, and various temperature and pressure sensors. Engine control units (ECU's) provide output signals to control the operation of various components related to the internal combustion engine of the marine propulsion system used to provide thrust for the marine vessel.
In marine vessels that use transducers as input devices, such as speed sensors, temperature sensors, and pressure sensors, it is typical for each transducer to be separately and individually connected in signal communication with an appropriate gauge located on the control panel at the helm of the vessel. For example, a speed measuring transducer (e.g. paddlewheel) may be connected by a pair of wires to a speedometer gauge on a control panel of the marine vessel. Similarly, a pressure transducer disposed in pressure sensing relation with an oil system or a cooling system would typically be connected by a pair of wires to a separate gauge on a control panel at the helm of the marine vessel. Similarly, temperature transducers and other sensors would be connected to their associated gauges on a control panel. If the marine propulsion system is provided with actuators to cause the propulsion system to trim or tilt relative to the marine vessel, switches would typically be provided at the helm to activate the trim and tilt cylinders and position transducers would be attached to the marine propulsion system and connected, by appropriate wires, to gauges on the control panel to inform the marine vessel operator of the actual position of the marine propulsion system.
In pleasure craft known to those skilled in the art, the various input and output devices are connected individually to associated devices. If many input and output devices are provided on the marine vessel, the number of wires and interconnections can be significant. In addition, during manufacture of the marine vessel, the assembly of the system can be very complex when large numbers of input and output devices are provided.
U.S. Pat. No. 3,958,524, which issued to Cantley et al on May 25, 1976, describes a station control selection system for controlling a motor and rudder of a power boat selectively from either of two remote stations, each of which includes means for producing linear input signals for motor shift and throttle control and for steering control. The system includes a steering input selector mechanism which is capable of transmitting the linear input signal for steering control from one of the stations to the rudder while isolating the signal from the other station. A motor input selector mechanism is capable of transmitting the linear input signals from motor shift and throttle control from one of the stations to the motor while isolating the signals from the other station. The steering and motor input selector mechanism may be actuated to facilitate the selection of one of the stations whenever corresponding linear input signals from the two stations are substantially equal. The system also includes a mechanism for initiating the actuation of selection of one of the stations prior to the corresponding linear input signals from the two stations being substantially equal.
U.S. Pat. No. 3,200,782, which issued to Walden on Aug. 17, 1965, describes a power boat attachment which prevents the tendency to porpoise, to increase speed at a given power and to improve tracking. The purpose of the invention is to provide elevator plates at the stern or transom of a power boat at the water line and to automatically adjust the angle of such elevator plates toward the horizontal by providing a regulator controlling the elevator plates and having cooperating plunger elements urged apart by a spring which yields and permits shortening of the regulator as more pressure is applied to the elevator plates by the water. A further purpose is to spring bias elevator plates located at the water line adjacent to the stern or transom of a power boat so that under low load the elevator plates extend behind the boat at a substantial angle below the horizontal and as load increases the springs yield to permit the elevator plates to assume smaller angles with respect to the horizontal.
U.S. Pat. No. 5,884,213, which issued to Carlson on Mar. 16, 1999, describes a system for controlling navigation of a fishing boat between waypoints representing successive positions around a navigation route. The system includes an input device for setting the waypoint positions, a position detector to detect the actual position of the fishing boat, a trolling motor to produce a thrust to propel the fishing boat, a steering motor to control the direction of the thrust, and a heading detector to detect the actual heading of the fishing boat. The system also includes a control circuit which determines a desired heading using a desired waypoint and the actual position of the fishing boat, and generates a steering control signal applied to the steering boat to steer the fishing boat from the actual position to the desired waypoint. The system operates in various modes which allow repeated navigation of the fishing boat around a navigational route. The system provides for automatic waypoint storage as the fishing boat is maneuvered around a navigation route.
U.S. Pat. No. 5,751,344, which issued to Schnee on May 12, 1998, describes a navigation system for a marine vessel in low light conditions and includes a low light video camera mounted with a weather proof enclosure on a vantage point of a marine vessel for improved night vision. A conventional video cameral is also mounted with the low light video for daytime viewing. Video signals from the cameras are automatically selected depending on light conditions for transmission to a cabin of the vessel. Motors rotate the housing in a horizontal plane and in a vertical plane for enabling remote controlled aiming of the cameras from the helm of the marine vessel. Sensors provide information on azimuth and elevation of the cameras for overlaying the video signal transmitted from the camera housing with this information for display with the video image on a monitor near the helm. Information on longitude and latitude, as well as vessel velocity and direction, from a global satellite positioning system receiver is also displayed. The overlay video signal is radio frequency modulated on to a predetermined channel for distribution to television receivers in other locations of the vessel.
U.S. Pat. No. 5,592,382, which issued to Colley on Jan. 7, 1997, discloses a directional steering and navigation indicator which directs a user toward a desired destination. Position and steering information are integrated into a single display to allow the user to immediately determine whether the correct course is being traveled, and to inform the user of any directional changes which may be necessary to be directed toward the desired destination waypoint. The user's position and course are determined by a navigation system and indicated on the display as a directional pointing icon, such as a line or arrow. The destination is displayed as a point. The user's Point of Closest Approach (PCA) can then be calculated according to current position, course, and the position of the desired destination. As the user's course gets closer to the bearing of the destination waypoint the PCA indicator can correspondingly shift with the user's movements. By superimposing the PCA over the destination waypoint, the user may precisely steer his or her craft to the desired destination.
U.S. Pat. No. 5,075,693, which issued to McMillan et al on Dec. 24, 1991, discloses a primary land arctic navigation system for use in a vehicle which comprises, in combination, a device providing a signal representative of the speed of the vehicle, and a computing apparatus responsive to the vehicle heading representative signal and the vehicle speed representative signal for providing a continuous indication of the position, altitude and heading of the vehicle.
U.S. Pat. No. 4,939,661, which issued to Barker et al on Jul. 3, 1990, describes an apparatus for a video marine navigation plotter with electronic charting and methods for use therein. The apparatus is provided for marine use and various methods for processing navigational data therein and displaying resulting navigational data thereon are provided. Specifically, the plotter stores coastline data only for those cells which contain coastline data within a given geographic region of a predefined chart. The data for each of these cells is stored in a unique data structure that stores data for a plurality of line segments that, when drawn, collectively depicts the geographic data stored within that cell. Each segment is stored in terms of coordinate locations for a starting point followed by coordinate offset values for each successive point in that cell. Only those cells and their constituent segments are drawn for coastline data that exists within a specific region to be displayed. Once a coastline chart is displayed, the inventive plotter permits navigational data to be overlaid thereon and through this capability provides several useful features as set forth in this description of this device.
U.S. Pat. No. 5,525,081, which issued to Mardsich et al on Jun. 11, 1996, discloses a transducer systems for a trolling motor. It comprises a trolling motor, including a microcontroller, a plurality of transducers, a steering motor, and an outboard motor. The user is allowed to input commands via a keyboard and the selected mode of operation is displayed via a LCD screen. The microcontroller operates the transducer to transmit sonar signals and the return signals are received and processed accordingly. In the preferred embodiment, there are five transducers arranged in a manner such that the port and starboard sides as well as the bottom of the boat are scanned continuously. The microcontroller processes the signals according to the user selected mode, determines the steering angle and the motor speed, transmits these values to the steering motor and position controller and the power drive and motor controller. In the preferred embodiment there are three automatic modes of operation: creek-tracking mode, depth-tracking mode, and shore-tracking mode.
Various types of known navigational systems utilize a global positioning system (GPS) which incorporates a plurality of earth orbiting satellites. The global position system (GPS) is a space-based radio navigation system consisting of numerous satellites and ground support stations. GPS provides users with accurate information about their position and velocity, as well as the time, anywhere in the world and in all weather conditions. The GPS, which was formerly known as the NAVASTAR Global Positioning System, was initiated in 1973 and is operated and maintained by the United States Department of Defense. The GPS determines location by computing the difference between the time that a signal is sent and the time that it is received. GPS satellites carry atomic clocks that provide extremely accurate time. The time information is placed in the codes broadcast by the satellites so that a receiver can continuously determine the time the signal was broadcast. The signal contains data that a receiver uses to compute the locations of the satellite and to make other adjustments needed for accurate positioning. The receiver uses the time difference between the time of signal reception and the broadcast time in order to compute the distance, or range, from the receiver to the satellite. With information about the ranges to three satellites and the location of the satellite when the signal was sent, the receiver can compute its own three dimensional position. By taking a measurement from a fourth satellite, the receiver avoids the need for having an atomic clock. Thus the receiver uses four satellites to compute latitude, longitude, altitude and time. GPS comprises three segments: the space segment, the control segment, and the user segment. The space segment includes the satellites which fly in circular order at an altitude of 12,500 miles and with a period of 12 hours. The orbits are tilted to the earth's equator by 55 degrees to ensure coverage of polar regions. Powered by solar cells, the satellites continuously orient themselves to point their solar panels toward the sun and their antennae toward the earth. Each satellite contains four atomic clocks. The control segment includes the master control station at Falcon Air Force Base in Colorado Springs, Colo. and monitor stations at Falcon Air Force Base and on Hawaii, Ascension Island in the Atlantic Ocean, Diego Garcia Atoll in the Indian Ocean and Kwajalein Island in the South Pacific Ocean. The user segment includes the equipment of the military personnel and civilians who receive GPS signals. Military GPS user equipment has been integrated into fighters, bombers, tankers, helicopters, ships, submarines, tanks, jeeps, and soldier equipment. Over 500,000 GPS receivers are in use at the current time. Surveyors use GPS to save time over standard survey methods. GPS is also used by aircraft and ships for en route navigation and for airport and harbor approaches. GPS tracking systems are used to route and monitor delivery vans and emergency vehicles. In a method called precision farming, GPS is used to monitor and control the application of agricultural fertilizer and pesticides. GPS is available as a in-car navigation aid and is used by hikers and hunters.
GPS is available in two basic forms. The standard positioning service (SPS) and the precise positioning service (PPS). SPS provides a horizontal position that is accurate to about 330 feet while PPS is accurate to about 70 feet. Enhanced techniques such as differential GPS (DGPS) and the use of a carrier frequency processing system have been developed for GPS. DGPS employs fixed stations on the earth as well as satellites and provides a horizontal position that is accurate to approximately 10 feet. Surveyors pioneered the use of a carrier frequency processing system to compute positions to within approximately 0.4 inches.
U.S. Pat. No. 5,467,282, which issued to Dennis on Nov. 14, 1995, describes a GPS and satellite navigation system. The system provides improved accuracy and reliability over wide geographical areas, including remote regions. Ranging type signals transmitted through two or more commercial geostationary telecommunication satellites are received at known reference locations where navigation and correction information is generated and transmitted back to remote users. At the same time, the reference stations receive signals from the global positioning system, generate corrections for the GPS measurements, then transmit these corrections to the remote user. The remote user receives all of this information plus direct measurement from both the GPS and the geostationary satellites and, using conditional error processing techniques, provides a position solution whose accuracy and reliability exceeds that of GPS alone. Alternatively, integrated carrier phase data can be substituted for pseudoranges obtained from the geostationary satellite transmissions.
U.S. Pat. No. 5,610,815, which issued to Gudat et al on Mar. 11, 1997, describes an integrated vehicle and navigation system for positioning and navigating an autonomous vehicle which allows the vehicle to travel between locations. Position information is derived from global positioning system satellites or other sources when the satellites are not in the view of the vehicle. Navigation of the vehicle is obtained using the position information, route information, obstacle detection and avoidance data, and on board vehicle data.
U.S. Pat. No. 5,983,159, which issued to Schipper on Nov. 9, 1999, describes a location determination system using signals from fewer than four satellites. The system can operate receiving signals from as few as one satellite, preferably non-geosynchronous. Where signals from two or more satellites are received, one may be geosynchronous. Pseudoranges are measured from one or more satellites at two or more selected, spaced apart observation times, and the simultaneous rotations of the body and the satellites relative to each other result in different body-satellite constellations for which the initial location coordinates of the selected point are determined exactly, without approximation or iteration. The selected point may be motionless or may be allowed to move with known coordinate differences between the initial unknown location and the present location at each observation time. Pseudoranges from different satellites, or even from different satellite systems can be measured and used in this procedure.
U.S. Pat. No. 5,955,973, which issued to Anderson on Sep. 21, 1999, discloses a field navigation system. A location system is used in a vehicle moving within an area at a selected speed and in a selected direction. A heading sensor provides a heading signal representing the direction of movements of the vehicle. A speed sensor provides a speed signal based on available reference signals representing the speed of the vehicle. A storage device stores initial position data representing a selected initial position of the vehicle and checkpoint data representing a navigation checkpoint location. A database stores a plurality of records which each include geographic information data representing selective aspects of the area. A processor estimates a current position signal representing an estimated current position of the vehicle based on values of the heading signal, values of the speed signal, the initial position signal, and on previous values of the current position signal. Values of the current position signal correspond to records stored in the data base. A correction device selectively corrects the current position signal based on selected position inputs which indicate an approximate vehicle position relative to the navigation checkpoint location. An alerting device obtains an alerting signal indicating that the vehicle has reached a selected region within the area based on the current position signal and the geographic information data.
U.S. Pat. No. 3,838,656, which issued to Greene on Oct. 1, 1974, discloses a marine automatic pilot rudder motor control system. The system for controlling the sensitivity of rudder movement on a pleasure boat having an automatic pilot is disclosed. The system includes apparatus for reducing the sensitivity of rudder responsiveness to error signals as wave motion and wind gusts increase.
U.S. Pat. No. 4,344,065, which issued to Erwin et al on Aug. 10, 1982, describes a convergence indicator for marine and flight vehicles. A visual aid for boat skippers to which a skipper inputs information about the relative position of another observed boat and a navigation light color which he observes is provided. The device has a group of input switches, each indicated a possible relative position of the second boat. Another group of switches indicates the possible navigation light colors of red, green, and white. A display signals whether the input combination of position and lights is a potential collision condition. A collision detecting logic circuit connects the switches to a display for actuating the display in response to actuation of selected combinations of the switches.
U.S. Pat. No. 5,390,125, which issued to Sennott et al on Feb. 14, 1995, describes a vehicle position determination system and method. The systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle is derived from satellites of a global positioning system and/or a pseudolite. The pseudolite might be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.
U.S. Pat. No. 5,155,490, which issued to Spradley et al on Oct. 13, 1992, describes a geodetic surveying system using multiple GPS base stations. The improved system and method for determining a position fix in space and time using the global positioning system satellite network signals is provided. The system comprises at least three fixed base stations each having a satellite receiver operating in conjunction with a highly accurate clock. Each base station's position is known with great accuracy. GPS Satellite signals are collected over statistically significant periods of time at each base station and fitted to determine with the clock offset and drift of the station clocks, thus establishing a network of base station clocks that in the aggregate is of great accuracy and precision. An arbitrary number of mobile receiver stations similarly collect date for working periods of statistically significant duration, with these data being used in conjunction with the base station data to compute position fixes for the mobile stations.
U.S. Pat. No. 5,014,206, which issued to Scribner et al on May 7, 1991, describes a tracking system for determining and recording the location of a vehicle during the occurrence of predetermined events. The vehicle is equipped with a sensor or sensors which respond to the occurrence of the predetermined events. The sensors are connected to a navigational system which receive positional information from a navigational transmitter. The navigational system then computes the positional information, such as latitude and longitude of the vehicle, and stores this information in a data collector on the vehicle. The date and time of day of the occurrence of the events may also be stored along with the positional information.
Many different types of chart plotters are commercially available and are well known to those skilled in the art. Various types of GPS plotters are available commercially and are manufactured by the Raytheon Corporation, the Furuno Corporation and others. In addition, many different types of hand-held and permanently fixed GPS receivers are available commercially.
A communication system known as the Controller Area Network (CAN) has been developed by the Bosch Corporation and has been used in many types of automotive and industrial applications. The basic principle of a CAN communication system is that data messages transmitted from any node on a CAN bus do not contain addresses of either the transmitting node or of any intended receiving node. Instead, the content of the message is labeled by an identifier that is unique throughout the network. All other nodes on the network receive the message and each performs an acceptance test on the identifier to determine if the message, and thus its content, is relevant to that particular node. If the message is relevant, it will be processed. Otherwise, it is ignored. A two-wire bus is usually provided and consists of a twisted pair of conductors. CAN is able to operate in extremely harsh environments and its extensive error checking mechanisms ensure that any transmission errors are detected. The National Marine Electronic Association (NMEA) has developed an international standard intended to permit ready and satisfactory communication between electronic marine instruments, navigation equipment, and communications equipment when interconnected via an appropriate system. The interconnection is intended to be by means of a two-conductor, shielded, twisted pair of wires.
U.S. Pat. No. 5,469,150, which issued to Sitte on Nov. 21, 1995, discloses a sensor actuator bus system. A four-wire bus is provided with a two-wire power bus and a two-wire signal bus and a plurality of sensors and actuators attached to both two-wire busses. A modification is provided to the standard CAN protocol developed and provided by Robert Bosch GmbH, in which the standard CAN header, of a data packet, is modified to incorporate a shortened device identifier priority. By shortening the identifier field of the CAN header three bits are made available for use as a short form protocol data unit which can be used to contain binary information representing both the change of status of an identified device and the current status of the device. The same three-bit PDU can be sued to acknowledge receipt of the change of status information. In order to retain all of the beneficial capabilities of the standard CAN protocol, the three-bit short form PDU can also be used to identify the use of additional bytes of a data field so that a device can take advantage of the more complex capabilities of the standard CAN protocol. However, in situations where a mere change of status report is sufficient, the present invention reduces the length of a message from a minimum of three bytes to a length of two bytes to obtain the significant benefits of increased speed of message transmission.
In certain systems, such as large industrial control systems, it may be sufficient to create a control system in which no new devices are expected to be added to the system after its initial design and manufacture. Alternatively, if the original manufacturer of the industrial control system retains control of all additional equipment added to the system, appropriate regulation of the signal exchanges can be retained. However, when one manufacturer originally creates a control system using CAN and other manufacturers add components to the system, without the knowledge of the original manufacturer, the orderly processing of signals and messages maybe compromised by the added components. Kvaser Consultant AB, of Sweden, and inventors Lennartsson and Fredriksson et al in particular have developed a system known to those skilled in the art as the "CAN Kingdom". The Can Kingdom system addresses several problems inherent in a standard controller area network system (CAN) when used in circumstances in which subsequent suppliers and users provide components that are later connected to an existing controller area network system and which are not under the control of the original manufacturer and supplier of the system.
U.S. Pat. No. 5,383,116, which issued to Lennartsson on Jan. 17, 1995, describes a device for controlling a member in a system. The apparatus or manufacturing system in which a first member executes a desired function or action which is controllable as a function of at least one parameter characteristic for a second member is provided by this system. A first detector detects signals corresponding to values of the at least one parameter of the second member. At least one transmitter receives the detected signals and assigns coded/numbered messages for each value of the parameter. The apparatus further includes at least one receiver with a control module for controlling the desired action of the first member. The signal transmission between the transmitter and the receiver occurs over a connection bus and the signals are transmitted in the form of the coded/numbered messages in a predetermined order, with well defined transmission times between the first detector and the transmitter and between the transmitter and the receiver. A control unit controls operation of the receiver module and sends thereto at least information regarding a desired parameter value at which a corresponding desired function or action is to be executed by the first member, or a desired message number to be selected. The receiver obtains the requested desired message number or, based on the desired parameter value and the time information for the desired action or function of the first member selects itself and receives a corresponding message number containing the parameter value. Based on the message number, the receiver generates an activation signal for the first member.
U.S. Pat. No. 5,446,846, which issued to Lennartson on Aug. 29, 1995, describes a distributed computer system arrangement. The system of interconnected module units which perform logical operations at different locations are included in the arrangement. A serial data bus interconnects all of the modules units through a connecting device which enables the module to communicate over the serial bus. The connecting device includes a memory device having stored therein identification information to identify the module unit to other module units communicating over the bus. A logic circuit which is connected to the memory device transfers the information from a memory to the module unit during an initialization phase of the system. The module units are thereafter able to communicate over the serial data bus. The connecting device has first and second sets of connectors for mating with corresponding connectors on the serial bus and the module units. Thus each module need not know where it is being connected along the serial bus, as all information for communicating over the bus is provided by the connecting device.
U.S. Pat. No. 5,696,911, which issued to Fredriksson on Dec. 9, 1997, describes an arrangement for eliminating malfunction and/or permitting high speed transmission in a serial bus connection, and transmitter and receiver units linked to the latter. The system includes a bus connection and transmitter and receiver units linked to this bus connection. The connection is digital and can assume one of two signal states, zero and one. Each unit assumes listening and transmitting positions and operates with an access function to the bus. Only designated or selected units can be activated so as to be able to transmit dominant signals or pulses, in this case zeroes. Said designated or selected units are located at a distance from each other which is substantially shorter than the total length of the connection. Dominant signals which can be assigned to the acknowledgement function in the system are emitted only by the selected or designated units. Other units are prevented from transmitting the respective dominant signal and assume only a listening position on the bus condition.
All of the patents described above are hereby explicitly incorporated by reference in the description of the present invention.
Many different types of input devices and output devices are available for use on a marine vessel and are well known to those skilled in the art. These devices include depth finders, fish finders, chart plotters, receivers, auto pilot systems, instrumentation gauges and annunciators, GPS receivers, and other navigational aids. These devices are individually well known to those skilled in the art and will not be individually described in detail herein. These input and output devices are available commercially from the Raytheon Corporation, the Motorola Corporation, and many other corporations.
Although each of the input and output devices described above are commercially available for use in conjunction with the control of marine vessels, it would be significantly beneficial if a communication system could be provided which allows all of the input and output devices to be conveniently and efficiently connected to a common serial bus in a way that allows a central controller to maintain control over all of the input and output devices and regulate the signal traffic on the serial bus. It would further be significantly advantageous if the serial bus could be configured in a way that allows additional components to be added subsequent to the original manufacture of the control system without adversely affecting the orderly operation of the control system. Of particular benefit would be the ability for a central controller to acknowledge and accept, or reject, the addition of input and output devices following the initial manufacture of the control system in conjunction with the marine vessel.